I put a set in the dash when I got my 03 cuz I missed the sound (from the dash area) of the infinity I had in my 02 1500 (same body).
I used base blockers on them and powered them with the HU, I upgraded the door speakers and powered them with an added amp under the drivers seat.
Many don't like the 6 speaker Infinity system but I do.
I think it has more to do with listening levels. At low to med sound levels it sounds fine to me but if you really like to crank it loud then that is where the infinity wont shine at all.